This paper investigates the empirical consequences for the relationship between skill upgrading and internationalization by decomposing import after country-of-origin and after the end-use of products. I find that the break-down after country-of-origin is of crucial importance, implying that international trade with low-wage countries leads to comprehensive skill upgrading, whereas international trade with high-wage countries leads to skill downgrading in Danish Manufacturing. The empirical literature on skill-upgrading and internationalization has mainly focused on international outsourcing and has to a large extent disregarded import penetration. By splitting import after country-of-origin, this reintroduces import penetration as an important explanation for skill upgrading. skill upgrading, import, country-of-origin, end-use of products